Kirk Johnson is the chief curator and vice president for Research and Collections at the Denver Museum of Nature and Science. He is a fossil-leaf specialist best known for his research on the global extinctions that happened 66 million years ago when a 6-mile asteroid struck what is now the Yucatán Peninsula of Mexico.
He is the author, with artist Ray Troll, of Cruisin’ the Fossil Freeway: An Epoch Tale of an Artist and a Scientist on the Ultimate 5,000-Mile Paleo Road Trip, which won the Colorado Book Award for best nonfiction in 2007.

In November of 2005, I gave a lecture about the relevance of paleoclimate
to modern global warming to an audience of nearly 1,000 oil and gas geologists
in Calgary. I had innocently assumed that their geologic knowledge
would predispose them to understand the significance of climate change. My
assumption was not correct. I was startled by the number of attendees who,
with their questions, rejected the idea that human activity had anything to
do with global warming. Many of them strongly objected to the methodology
of using mathematical climate models to predict future climate trends.
The pairing of paleoclimate records with climate models creates a smooth
framework from the past through the present to the future that allows the
creation of testable hypotheses about climate processes. This is solid science
with tremendous potential, yet several of the questioners responded to it
with dogmatic denial. I had clearly misjudged my audience and it made me
want to understand what was going on that would cause such an emotional
response to a series of scientific observations and predictions.